An infinite dimensional Schur–Horn Theorem and majorization theory

An infinite dimensional Schur–Horn Theorem and majorization theory

The main result of this paper is the extension of the Schur–Horn Theorem to infinite sequences: For two nonincreasing nonsummable sequences ξ and η that converge to 0, there exists a positive compact operator A with eigenvalue list η and diagonal sequence ξ if and only if ∑n j=1 ξj ∑n j=1 ηj for every n if and only if ξ = Qη for some orthostochastic matrix Q. When ξ and η are summable, requirin...

An Infinite Dimensional Schur-horn Theorem and Majorization Theory with Applications to Operator Ideals

The main result of this paper is the extension of the Schur-Horn Theorem to infinite sequences: For two nonincreasing nonsummable sequences ξ and η that converge to 0, there exists a positive compact operator A with eigenvalue list η and diagonal sequence ξ if and only if Pn j=1 ξj ≤ Pn j=1 ηj for every n if and only if ξ = Qη for some orthostochastic matrix Q. When ξ and η are summable, requir...

An Infinite Dimensional Convolution Theorem

An Infinite Dimensional Convolution Theorem

An Infinite Dimensional Convolution Theorem